The second edition of Canal Mania is changed in a number of ways from the first edition including

Revised board with different colour distribution for towns and inclusion of Newark instead of Llangollen.
Revised Contract deck + introduction of Junction contracts.
Narrow Boat pieces in place of First edition "Tugs"
Revised scoring for completed Canals.

Further info http://www.ragnarbrothers.co.uk/html/2nd_edition_canal_mania.html